Unlike alcohol or other drug abuse where those under the influence may appear intoxicated or "high", problem gamblers usually do not exhibit easily recognizable signs. However, there are signs that may indicate someone is experiencing a gambling problem.

According to the South Oaks Gambling Screen (SOGS), the following are often signs of problem gambling:

• The person gambles more than they intended
• Other people are suggesting that the person might have a gambling problem
• The person is feeling guilty about the way he or she gambles
• The person wants to stop betting money and feels like he or she can’t
• The person gambling is hiding betting slips, lottery tickets, gambling money or other signs of betting
• There are arguments over how the person gambling is handling money
• The person gambling is borrowing money and not repaying it
• The person gambling is losing time from work or school due to betting money or gambling

The American Psychiatric Association's Diagnostic Statistical Manual of Mental Disorders (DSM-IV), also suggests that signs of problem gambling may include:

• Preoccupation with gambling (reliving past gambling experiences, planning the next venture or thinking of ways in which to gamble)
• Needing to gamble with increasing amounts of money in order to achieve the desired excitement
• Trying to control, cut down or stop gambling unsuccessfully
• Feeling restless or irritable when attempting to cut down or stop gambling
• Using gambling as a way to escape problems or bad moods (helplessness, guilt, anxiety, depression)
• Returning to gamble after losing money gambling
• Lying to conceal the extent of involvement with gambling
• Committing illegal acts, such as forgery, fraud, theft or embezzlement to finance gambling.
• Jeopardizing or losing a significant relationship, job, educational or career opportunity because of gambling.
• Relying on others to get out of debt